CLEARY, M.E.; MARSH, R.L.; ELLERBY, D.J.; BUCHANAN, C.I.: Maximal oxygen consumption in running Guinea fowl.
Maximal oxygen consumption (VO2, max) during running has been measured in numerous mammals, but few values exist for birds. VO2, max provides an important benchmark for judging the metabolic effort required at a particular speed. Published values of VO2, max in rheas have suggested the hypothesis that birds have maximal aerobic scopes much greater than those found for mammals. We measured oxygen consumption and carbon dioxide production of domestic Guinea fowl weighing approximately 1.5 kg. Birds were run on a motor driven treadmill on the level as well as up slopes of 10 and 20%. During level running, the birds reached a VO2, max of approximately 155 mlO2/min at speeds between 2.5 and 3.5 m/s. When they ran uphill, a similar VO2, max was measured but at a lower speed. VO2, max of these birds is approximately 10-12 times their predicted basal metabolic rate, a value near the mean aerobic scope of mammals. However, Guinea fowl have a smaller muscle mass devoted to running than do mammals or large flightless birds such as rheas. Nevertheless, the performance of these birds does not support the hypothesis that birds have unusually high aerobic scopes. Supported by NIH grant AR47337.
